Porosity is a measure of void spaces in a material. It can be measured with porosimeters, optical methods, geometric or mass considerations. For years these methods have been developed by many researchers, although they still have some limitations. The clue of the problem is a proper determination the pores’ volume. The mentioned techniques are able to determine the porosity of a clean fabric. However, porosity of a fibrous structure decreased by the accumulated deposit is problematic. The techniques founded on a flow-through or immersion could destroy and relocate formed agglomerates, thus produce false results. The only possibility of a non-destructive evaluation of this parameter is by the use of X-ray tomography. But, in case of a submicron-sized contamination, the usage of this technique is limited to rather qualitative results. The quantitative measurement of porosity development inside a fibrous filter during the filtration process was never before a subject of detailed considerations although, it has a crucial impact on particle transport phenomena. In this work a quantitative description of filter porosity development based on the initial value of porosity, scanning electron microscope images and the overall filter mass was proposed. Experiments were performed for different fibrous structures. Results indicate, that...
Session: L5 - Depth Filtration - Modelling and Design
Day: 14 March 2018
Time: 09:00 - 10:15 h